Ballast water recovery for airships



April 27, 1937. w. o. 1.. FISCHER 2,073,532

BALLAST WATER RECOVERY FOR AIRSHIPS Filed Jan. 27, 1954 Elam/MM;

Patented Apr. 27, 1937 UNITED STATES 2,078,532 BALLAST WATER RECOVERY FOR AIRS HIPS

Wilhelm 0. L. Fischer, Akron, Ohio, assignor to Goodyear-Zeppelin Corporation, Akron, Ohio, a corporation of Delaware Application January 27, 1934, Serial No. 708,596

6 Claims.

This invention relates to airships and particularly to airships which are inflated with helium and hydrogen or exclusively-with hydrogen as a lifting gas and has for its object the improvement of airship efficiency.

The lifting powerof an airship on the ground greatest when the gas cells are fully inflated at atmospheric pressure. Airships operated with hydrogen usually are completely or hundred per cent inflated at the take-off and because of its relatively low cost, the gas when expanded at higher altitudes and lower air pressure is simply discharged into the atmosphere. Helium airships, on the other hand, are inflated only to a certain percentage of their gas cell capacityto permit the expensive helium to expand within the cells rather than be discharged. This incomplete inflation, of course, reduces the lifting power perceptibly. To this lift reduction must be added the lower lifting power of helium, which is approximately ten per cent below that of hydrogen.

However, helium has the great advantage of being non-inflammable and therefore is preferred as a lifting gas.

It has been proposed to improve the efliciency of helium-infiated airships by adding gas cells inflated with hydrogen which are protected by the surrounding helium. This procedure makes it possible to fully inflate the gas cells and to' valve off the cheaper hydrogen instead of the expensive helium when the gases expand. In order to keep the ship in trim it has moreover been necessary in most prior airships to discharge some of the gas to compensate for the weight of liquidfuel consumed by the internal combustion engines used to propel the airship. The discharged gas, of course, is lost. Instead of simply discharging the hydrogen, attempts have been made to burn it either alone or together with liquid fuel in an internal combustion engine. However, these attempts have not given satisfactory results, because suitable engines for that purpose are not available.

Another method for keeping the buoyancy of the airship constant as much as possible has been successfully applied in helium-inflated airships by recovering the water contained in the exhaust gases discharged from the internal combustion engines, which furnish the propelling power. Under favorable conditions sufficient water can be recovered to compensate for the weight of fuel and oil consumed. However, the condensers, for cooling the water vapor contained in the exhaust gases down to the dew'point, must be very large impurities, which make it impossible to use the water for washing, drinking, cooln'ng, etc. The impurities also deposit on the condenser walls decreasing the heat dissipation through the walls and the gases further tend to attack and destroy the metal of the condensers by corrosion in a relatively short time. I

The present invention is a decided improvement over known methods of keeping an airship in proper buoyancy and relies on a new and novel water recovery system. It avoids and overcomes the imperfect and objectionable features of former methods of recovering water from propelling motor exhaust gases and also accomplishes the recovery of a greater amount of actually pure water with a much smaller condenser system which weighs considerably less. Instead .of recovering the combustion produc of the hydrogen contained in the liquid fuel which additional power for propelling the ship in conjunction with the usual internal combustion engines operated by gasoline or oil. The combustion product obtained by this new method consists only of water vapor which is mixed with the nitrogen of the combustion air. The resulting condensate is ,very pure water.

much water as one pound of the exhaust gases from the ordinary internal combustion engines. This is because the exhaust gasesfrom the ordinary internal combustion engine include considerable quantities of carbon dioxide and other gases having little or no water content. The combustion products of the hydrogen are on the other hand substantially all water.-

Due to the fact that the hydrogen gas is completely burned and its water combustion product is recovered, a relatively small volume of hydrogen will be required'for compensating the weight of the liquid fuel consumed by the internal combustion engines. Thewatr recovered from the flue gases of the burnt hydrogen will be fully sufficient for compensating the weight of the liquid fuel without resorting to recovering the water contained in the liquid fuel engine exhaust gases. The condenser surface can also be very much smaller whereby the water recovery system is considerably simplified and its weight greatly reduced with a resulting lowering of cost.

Because the water recovered is almost perfectly pure, the fresh water supply to be carried on the ship can be much reduced and payable load carried instead. A soot separator is dispensed with and the condenser is always in clean condition. Another advantage is the uniform and even flow of the flue gases through the condenser avoiding the pulsation of the exhaust from the One pound of the boiler flue gases contains about three times as internal combustion engines which fatigue and shorten the life of the material forming the condenser.

For a better understanding of this invention reference may be had to the accompanying drawing, wherein.

Fig. 1 shows diagrammatically a side view of an airship with the covering partly removed to better illustrate the invention;

' Fig. 2 shows a front view of the airship.

Referring to the drawing, Fig. 1 illustrates an airship 5 which is equipped with a liquid fuel supply I for feeding the internal combustion power units 9 which provide the main propelling power for the airship. The interior space l2 of the airship 5 is usually divided up into a number of compartments which contain the lifting gas, either helium or hydrogen generally enclosed in individual gas cells (not shown). In case helium is used as main lifting gas, relatively small gas cells l3 containingthe inflammable hydrogen are disposed within the non-inflammable helium.

The hydrogen of course serves as lifting gas during flight but it can, as desired, be fed as fuel by a pipe line M to a steam generator 15 where it is burnt to change the water in the generator to steam. A pipe line l6 leads the generated steam to a steam engine l1, preferably of the turbine type, which furnishes additional propelling power. The exhaust of the steam engine passes through a pipe line l8 into a condenser I9 from where it is returned in condensed state into the steam generator by a conduit 20.

The flue gases formed by the hydrogen burnt} at the steam generator I5 are conducted by a pipe line 2| into a second condenser 22 from which the condensate, pure water, is drained by a pipe line 5 used for drinking, cooking and the like as it is i very pure. Since the exhaust steam from the turbines carries few if any impurities, the invention contemplates under certain conditions if desired combining the condenser for the exhaust steam and the condenser for the fine gases into a single unit.

From the foregoing description, it will be apparent that I have devised a very eificient and most simple method for automatically obtaining pure ballast water. While I have shown only one form my invention, may assume it will be apparent to those skilled in the art that it is not so limited but that various modifications and changes may be made therein without departing from the spirit of my invention or from the scope of the appended claims.

What I claim is:

1. In combination with an airship, lifting-gas compartments containing helium, at least one lifting-gas compartment containing hydrogen, the hydrogen compartments being surrounded by helium, means containing liquid fuel, a steam power plants including an external combustion motor for burning some of said hydrogen exclusively without contamination, an internal combustion power plant operated by the liquid fuel, a condenser for condensing the water vapor formed by the burning of the hydrogen, water containers for storing the condensed water, and a second condenser for condensing the exhaust steam from the steam power plant, said steam and internal combustion power plants being so proportioned to each other that the amount of condensate collected will substantially equal in weight the amount of liquid fuel used, minus the amount of lift of the gaseous fuel burned.

2. In combination with an airship, lifting-gas compartments containing helium, lifting-gas compartments containing hydrogen, the hydrogen compartments being surrounded by helium, an external combustion power plant using hydrogen lifting gas exclusively for fuel, a condensersystem for condensing the combustion product of the hydrogen into water fit for human consumption, and water containers for storing the recovered water to thereby keep the ship in trim and to offset the use of ballast, drinking, cooking or like Water, and taking into account any loss of lifting eifect of the gas.

3. In combination with an airship, of liftinggas compartments containing helium, liftinggas compartments containing hydrogen, the hydrogen compartments being surrounded by helium, means containing liquid fuel, an external combustion power plant using-said hydrogen exclusively for fuel, an internal combustion power plant operated by the liquid fuel, a condensersystem for condensing the combustion product of the hydrogen into water fit for human consumption, and water containers for storing the recovered water to thereby keep the ship in trim and to offset use of ballast, drinking, cooking, washing or like water, and taking into account any loss of lifting effect of the lifting gases in the ship.

4. The combination with an airship using a combustible gas, at least in part, for lifting said airship, of an external combustion motor plant on said airship for burning said combustible gas which, when burned, is substantially entirely reduced to water fit for human consumption, an internal combustion power plant using liquid fuel, and a ballast water recovery system for condensing the product of combustion of the gaseous fuel into water and storing the recovered water on said airship to thereby maintain the balance of the airship by compensating for loss of the liquid fuel as it is used.

5. That method of maintaining substantially constant the buoyancy of a lighter-than-air aircraft, using a combustible gaseous fuel at'least in part for lifting, which comprises employing external and internal combustion motors on the aircraft for propulsion purposes, using liquid fuel for the internal combustion motor, using some of said combustible lifting gas for fuel in the external combustion engine, the gaseous fuel being one which when burned is substantially entirely reduced to water, and condensing and storing the water so formed to compensate for loss of fuel burned in the internal combustion motor.

6. The method-of supplying an airship, using a burnable water producing lifting gas 'at least in part, with water fit for human consumption, comprising the steps of burning at least part of said gas in an-external combustion power plant onsaid airship out of contactwith matter which would contaminate same to an extent which would render it unfit for the purpose set forth, condensing the water vapor formed by said burning, and utilizing the energy developed in said power plant for airship operations.

WILHELM O. L. FISCHER. 

